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Instruction Manual Instruction Manual Maksutov Telescope 90/1250 OTA English version 10.2014 Rev A Reproduction of part or all of the contents of this document in any form is expressly prohibited other than for individual use only. All text, images and labels are property of Nimax Gmbh. The Omegon® Maksutov Telescope 90/1250 OTA Congratulations on the purchase of the new Omegon® Telescope Maksutov 90/1250 OTA. This telescope tube is suited for both terrestrial and astronomical use. It is compact and easy to carry around; it can also be used as a tele-objective or a high-power telescope. You can even use it to take photos with a DSLR camera (not included). 1. Included parts. Besides the telescope tube we have included a finderscope, a finderscope bracket and a soft carry case. 2. Getting started. It is very simple to get started. Here is how the telescope works. The telescope aperture (lens) should be pointing to the object being observed. The light comes through the aperture lens, to the mirror on the back and is then reflected to the small secondary mirror on the telescope lens. There it is reflected again and so brought to the eyepiece. The eyepiece can be used in two positions – top (#5) or back (#6) – see below. At the focuser one can use accessories. Different accessory combinations give different results, such as different image magnifications. All this will be explained in detail on the next pages. 2.1. Knowing your telescope. 1- Optical Tube; 7- Finderscope adjustment screw; 2- Dovetail adapter for telescope mount or tripod; 8- Focusing knob; 3- Finderscope adjustment screw; 9- Flip-Mirror System; 4- Finderscope; 10- DSLR Camera (not included); 5- Top eyepiece holder; 11- T-ring adapter (not included); 6- Back eyepiece holder; 12- Eyepiece (not included). 3. Assembly. Remove the telescope from the shipping box. Start by installing the finderscope tube and finderscope bracket as shown in figure 1. Make sure it is pointing to the telescope’s aperture, tighten it using the side finderscope thumbscrew (on the finderscope shoe base). You will need to use a photographic tripod or a telescope mount (Vixen/Synta compatible dovetail) to mount the tube (figure 2). Make sure you choose a stable tripod or mount for ease of use. The telescope’s aperture should point to the object being observed. Choose a low magnification eyepiece (#12), insert it into the top eyepiece holder (#5), and make sure to securely tighten the eyepiece using the eyepiece holder thumbscrew. You may also use the eyepiece on the back eyepiece holder (#6). Use the focusing knob (#8) to get a sharp (focused) image. The back eyepiece holder (#6) provides a straight view for a DSLR camera. To use a DSLR camera with the telescope start by removing the Reproduction of part or all of the contents of this document in any form is expressly prohibited other than for individual use only. All text, images and labels are property of Nimax Gmbh. camera objective lens and place the T-ring on the camera body (#11), thread the camera to the telescope back eyepiece holder (#6), it should look like figure 3. The telescope includes a spring- loaded flip-mirror system (figure 4). Switch from horizontal to vertical position to get straight- through view, or from vertical to horizontal position to get top view (figure 4). Figure 1. Install the finderscope. Figure 2. Place the tube on a suitable tripod or mount. Figure 3. Telescope ready for imaging (camera, mount Figure 4. Flip mirror horizontal (light comes through back - and eyepiece not included). #6 suitable for DSLR use). ATTENTION! Never look at the Sun through a telescope. Concentrated Sun light may cause serious eye injury. Children should use with adult supervision only! 4. How to use and how to align the finderscope? Reproduction of part or all of the contents of this document in any form is expressly prohibited other than for individual use only. All text, images and labels are property of Nimax Gmbh. 4.1. A distant object is centered at the telescope’s field of view with an eyepiece. In this example we have a house with a chimney. The chimney is the reference point to place at the center of the field of view. We first look through the telescope with the lowest magnification possible to get the widest field of view. 4.2. Looking through the finderscope we see the same building, but in this case the chimney is not centered. We adjust the finderscope using the three thumbscrews, so that the finderscope moves slightly. This is enough to correct the objects position in the finderscope. Trial and error is required to get a satisfactory result. Make sure to tighten the 3 screws after finishing, so that the finderscope tube does not move. 4.3. After playing with the three findercope thumbscrews and some trial and error we get the finderscope’s recticle close to the center (in this case the chimney). The finderscope is now ready to use! 5. What can be seen with this telescope? Reproduction of part or all of the contents of this document in any form is expressly prohibited other than for individual use only. All text, images and labels are property of Nimax Gmbh. Below you will find some examples of what you can expect to see when using this telescope. 5.1. The Moon is one of the most spectacular objects to be seen through a telescope. Even a small telescope will reveal a lot of details of the Moon’s surface. You will be able to see the craters on the Moon’s surface and other features like the Marea. The moon is a very bright object. It is better observed when the Moon is not full. Try the crescent Moon and look for features along the terminator (between illumated and dark surfaces). 5.2. Jupiter is the biggest planets of our solar system. It is also one of the most favorite targets for beginners. Galileo was able to discover that the four tiny dots that circle around the planet were in fact part of Jupiter’s system of moons. With this telescope you will not only be able to see Jupiter’s planet disc with its two major discernible bands, but also its biggest moons, Io, Europa, Ganymedes and Callisto. 5.3. The “lord of the rings” of the night sky, Saturn is by far the most popular target for small telescopes. Saturn’s rings are discernible even at 60x magnification. In a very good night you will be able to see the Cassini’s division (the darker band of Saturn’s rings). Reproduction of part or all of the contents of this document in any form is expressly prohibited other than for individual use only. All text, images and labels are property of Nimax Gmbh. 6. Using the accessories: a bit of math to Telescope’s focal length is 1250mm; understand how it all works. Omegon® Plössl 25mm eyepiece’s focal length is 25mm; Using accessories is easy and fun. To change the magnification simply swap eyepieces. To get more magnification simply use the barlow 1250푚푚 = 50 푝표푤푒푟 lens. But how does all of this work? 25푚푚 6.1. Power (magnification) Your telescope has a focal length of 1250mm. This means that the 25mm eyepiece provides This is approximately the distance between a 50x power (magnification). This seems low, the telescope lens and its focal point (very but try it, you will see a bright image with similar to the distance between the focus details. point of a loupe and the loupe lens). This is a 6.2. Barlow Lens (not included) very important feature, that allows to determine several interesting facts such as The barlow lens is a very interesting device magnification. (not included). It is a negative lens, that multiplies the telescope’s focal length. A 2x The magnification is determined by the Barlow, for example, multiplies the original telescope’s focal length and the used focal length by 2x, in this case 1250푚푚 푥 2 = eyepiece. 2500푚푚. To determine the magnification just divide the A 3x Barlow lens multiplies by 3x. telescope’s focal length by the eyepiece’s When used with a 25mm eyepiece you get 2x focal length. Let’s give an example for our the power obtained before telescope and some eyepieces: 50 푝표푤푒푟 푋 2푥 퐵푎푟푙표푤 = 100 푝표푤푒푟 Here are some examples on how to use the accessories. Some possible accessory combinations Terrestrial Moon Deep Sky Jupiter and View Saturn Omegon® Plössl 25mm Yes Yes Omegon® Plössl 9mm Yes Omegon® LE 12.5mm Yes Omegon® Moon Filter Yes Omegon® UHC Filter Yes Power 50x 139x 50x 100x Technical notes The two top and back eyepiece exit holders are not parfocal. The back eyepiece holder (#6) requires an additional 5mm spacing to be parfocal with the top. We recommend using a 1.25” (31.75mm) parfocalizing ring, if required. For both DSLR use and eyepiece use we recommend using a 1.25” eyepiece extender at the top eyepiece holder (#5) to push the eyepiece out and make it parfocal with the camera. Reproduction of part or all of the contents of this document in any form is expressly prohibited other than for individual use only. All text, images and labels are property of Nimax Gmbh. 7. Troubleshooting and frequently asked questions Q: I can’t focus my telescope, but only get a bright circle. R: Make sure you have inserted the eyepiece (start by the lowest power eyepiece). Point to a distant object during the day and proceed as described in 3.
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